From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-7.6 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,NICE_REPLY_A,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 3370FC43460 for ; Mon, 17 May 2021 16:44:25 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 1990D611B0 for ; Mon, 17 May 2021 16:44:25 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S241731AbhEQQpk (ORCPT ); Mon, 17 May 2021 12:45:40 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]:44107 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S240562AbhEQQp3 (ORCPT ); Mon, 17 May 2021 12:45:29 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1621269842; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=pLOobSjCbQskFqMnll0HyKDl5KNjQO+RBewEeO7jSSc=; b=G1vgcO12YGKD0d0osMoY3g3sTP30iMUiNJbgGdS5JEbqJRjR7mhPHOhQElILTX4mfjGTbd vtmj6nNLN5QOS3zTFrWJMBuv0TRpz4cBqLhQNJ7cc1D6LM7sWwby7mkCtBnyKopsns1ERY Km8PQDNDUfD4eVhfxNxwGGDnTiQaLgs= Received: from mail-ej1-f70.google.com (mail-ej1-f70.google.com [209.85.218.70]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-208-fiDcW9MlOVSdo-5D5yidxg-1; Mon, 17 May 2021 12:44:00 -0400 X-MC-Unique: fiDcW9MlOVSdo-5D5yidxg-1 Received: by mail-ej1-f70.google.com with SMTP id m18-20020a1709062352b02903d2d831f9baso1257426eja.20 for ; Mon, 17 May 2021 09:44:00 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:subject:to:cc:references:from:message-id:date :user-agent:mime-version:in-reply-to:content-language :content-transfer-encoding; bh=pLOobSjCbQskFqMnll0HyKDl5KNjQO+RBewEeO7jSSc=; b=CD15Sa8RLlTxXKNj9edXSne2I+KbidQ93w/mEJxGel04w5U8AsHTRr33uDKvDn0LHW 1SghceJ765//LJfDVdqJ8+y+AbQmpH/eovN2CH+T4p4g/j6ar4pDF4cFpWV5h58IGIsb 9wPBhYaQHQHhBlIjZA1iHXx1eKpb4FH9flhCVJmVYpWJ5+PKMUaz6zuv3S+g4buEVM+O AGmolCk8bdDw2CKnsl/g8HSkJMbv7v5wC4LianJ95h3gGczcb86/JM9nz3YIqmrzDIM8 O25L0sWqIgdRIb3nB39ENhir5m6zpLHzR4f5gIYls0B/so3fJllGVHo4UgRhNHMVgPHQ wh9Q== X-Gm-Message-State: AOAM532nvMTCkz3IkQZ0z8F8Wk7pV/Um0/fW5+qkNJLInfdWyNU8jl9O 7Q0sXpJW0yfEmpoSZLy7o7N0/d5k0REgjHDfWERRTgqo32IiS3SMD7+VPyfAaVJ2OMY35XId+3y 4owMNguipoDSBdlcYB/UvIYo9Per0Ody0dT00jrArJ+9mRoeM3KyRTXd5fYj5lMLY X-Received: by 2002:a50:cdd1:: with SMTP id h17mr1150021edj.178.1621269839239; Mon, 17 May 2021 09:43:59 -0700 (PDT) X-Google-Smtp-Source: ABdhPJybcPfcPZg8fUCw2rYDP5qsCQxq7rGzcUbcnUmTWFmLAlzNQpmPlCsCiTwFNHTun2K89RcSNQ== X-Received: by 2002:a50:cdd1:: with SMTP id h17mr1149967edj.178.1621269838988; Mon, 17 May 2021 09:43:58 -0700 (PDT) Received: from ?IPv6:2001:b07:6468:f312:c8dd:75d4:99ab:290a? ([2001:b07:6468:f312:c8dd:75d4:99ab:290a]) by smtp.gmail.com with ESMTPSA id i5sm4826603edt.11.2021.05.17.09.43.56 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Mon, 17 May 2021 09:43:58 -0700 (PDT) Subject: Re: [PATCH] KVM: x86: add hint to skip hidden rdpkru under kvm_load_host_xsave_state To: Dave Hansen , Andy Lutomirski , Jon Kohler Cc: Babu Moger , Thomas Gleixner , Ingo Molnar , Borislav Petkov , X86 ML , "H. Peter Anvin" , Sean Christopherson , Vitaly Kuznetsov , Wanpeng Li , Jim Mattson , Joerg Roedel , Fenghua Yu , Yu-cheng Yu , Tony Luck , Uros Bizjak , Petteri Aimonen , Kan Liang , Andrew Morton , Mike Rapoport , Benjamin Thiel , Fan Yang , Juergen Gross , Dave Jiang , "Peter Zijlstra (Intel)" , Ricardo Neri , Arvind Sankar , LKML , kvm list References: <20210507164456.1033-1-jon@nutanix.com> From: Paolo Bonzini Message-ID: Date: Mon, 17 May 2021 18:43:56 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101 Thunderbird/78.8.1 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org On 17/05/21 15:54, Dave Hansen wrote: > On 5/13/21 10:11 PM, Andy Lutomirski wrote: >> I don't even want to think about what happens if a perf NMI hits and >> accesses host user memory while the guest PKRU is live (on VMX -- I >> think this can't happen on SVM). > > What's the relevant difference between SVM and VMX here? I'm missing > something. SVM has the global interrupt flag that blocks NMIs and SMIs, and PKRU is loaded while GIF=0. Paolo